const target = { foo: 'bar' };
const proxy = new Proxy(target, handler);
console.log(proxy.foo); // Output: Getting property foo, then "bar" proxy.foo = 'baz'; // Output: Setting property foo to baz console.log(proxy.foo); // Output: "baz" In this example, we create a target object with a single property foo . We then define a handler object that intercepts get and set operations on the target object. Finally, we create a proxy instance, passing in the target and handler objects. proxy made with reflect 4 2021
Here's an example of how you might use a proxy to implement a simple cache:
const target = { expensiveComputation: () => { // simulate an expensive computation return new Promise((resolve) => { setTimeout(() => { resolve(Math.random()); }, 2000); }); } }; const target = { foo: 'bar' }; const
Creating a proxy with Reflect 4 2021 is straightforward. Here's an example:
const handler = { get: (target, prop) => { if (prop === 'expensiveComputation') { if (cache.has(prop)) { return cache.get(prop); } else { const result = target[prop](); cache.set(prop, result); return result; } } return Reflect.get(target, prop); } }; Here's an example of how you might use
console.log(proxy.expensiveComputation()); // takes 2 seconds console.log(proxy.expensiveComputation()); // returns cached result immediately In this example, we create a proxy that caches the results of an expensive computation. The first time the expensiveComputation method is called, the proxy computes the result and caches it. Subsequent calls return the cached result immediately.